Field longevity of methyl eugenol and cue-lure plugs and associated insecticidal strips: captures of Bactrocera dorsalis and Zeugodacus cucurbitae (Diptera: Tephritidae) in Hawaii.

The article focuses on evaluating the longevity and effectiveness of slow-release polymeric plugs containing male-specific lures methyl eugenol (ME) and cue-lure (CL) for trapping two species of true fruit flies, Bactrocera dorsalis and Zeugodacus cucurbitae, which cause significant damage to commercial fruits and vegetables. The study found that ME plugs remained as effective as fresh liquid ME for attracting B. dorsalis males up to 12 weeks of weathering but declined in effectiveness at 18 and 24 weeks. Similarly, CL plugs were effective for attracting Z. cucurbitae males up to 18 weeks but not after 24 weeks. Chemical analyses showed a decrease in residual ME content over time, correlating with reduced trap captures, while CL content remained relatively stable despite decreased attractiveness after 24 weeks, indicating complexities in linking lure release rates to trapping efficacy. These findings inform the development of more durable and practical monitoring tools for invasive fruit fly species.